The invention relates to an indicating device with a pointer. In the case of this indicating device, the pointer comprises a rotary pointer spindle and a pointer vane arranged radially on the pointer spindle, the pointer vane being deflected according to a rotation of the pointer spindle.
Indicating devices of this type are sufficiently known from various instances of use. They are to be found for example in indicating instruments in motor vehicles. In the case of these indicating devices, the pointer vane is rigidly connected to the pointer spindle. In some designs, the pointer vane is formed as a light guide and can be illuminated if need be. It has been found, however, that a pointer vane illuminated in such a way only has low contrast when there is bright ambient light and, as a consequence of this, also produces only a weak signaling effect in certain situations, so that a pointer vane of this type of design is not very well suited for reliably assuming the function of a warning device in addition to its conventional indicating function, even if light of different colors or intensities were fed into the pointer vane formed as a light guide to indicate a specific warning. Configurations of indicating devices of the generic type with a pointer vane provided with a colored coating are also known, but a signaling effect that can be used for a warning device is not in fact obtained from a pointer vane which is connected to a pointer spindle and has a permanent, unchangeable form of colored surface.
It is consequently the object of the present invention to develop further an indicating device of the introductory-mentioned type with a pointer in such a way that, in addition to its conventional indicating function, the pointer vane can be used as a warning device reliably and with an adequate signaling effect.
The object is achieved by an indicating device of the introductory-mentioned type, wherein, in addition to its ability to pivot as a result of the rotation of the pointer spindle, it is also rotatable about the axis of its radial extent and the pointer vane has at least two boundary surfaces which can be distinguished from one another in their appearance. The solution accordingly envisages that the boundary surfaces of the pointer vane are used for indicating at least two signaling states that can be clearly distinguished from one another. According to the angle of rotation of the pointer vane about the axis of its radial extent, a signaling effect consequently emanates from the boundary surfaces of the pointer vane, so that, in addition to its conventional indicating function, the pointer vane can be used as a warning device.
The indicating device may be configured in such a way that the rotation of the pointer vane about the axis of its radial extent is independent of the rotation of the pointer spindle. There is accordingly no link between the angle of rotation of the pointer spindle and the angle of rotation of the pointer vane. Such a configuration has the advantage that the function of the pointer vane as a warning device can be performed independently of the conventional indicating function of the pointer vane.
Permanently magnetic or electromagnetic actuating means are suitable in particular as the drive for rotating the pointer vane about the axis of its radial extent, because they can be realized inexpensively. At the same time, the permanently magnetic actuating means may comprise for example a two-pole actuating magnet arranged on a shaft of the pointer vane and a permanent magnet formed annularly around the pointer spindle and having at least two different polarity zones. The electromagnetic actuating means can be formed. by a two-pole actuating magnet arranged on a shaft of the pointer vane and an actuating coil through which current can flow and which is formed annularly around the pointer spindle. The use of permanently magnetic actuating means is a solution which is simple and inexpensive to realize if the function of the pointer vane as a warning device is to be performed in a fixed dependence on a specific angle of rotation of the pointer spindle. If the function of the pointer vane as a warning device is to be controllable independently of the angle of rotation of the pointer spindle, electromagnetic actuating means in which the current flow through an actuating coil can be controlled in order to produce the. warning signal, constitute the adequate solution. For the structural configuration, it is. advantageous if the shaft of the pointer vane is rotatably mounted in the pointer spindle itself or in the extension thereof firmly connected to it. The shaft of the pointer vane is firmly connected to the body of the pointer vane.
To use the pointer vane as a warning device in addition to its conventional indicating function, the pointer vane may have along the axis of its radial extent at least two boundary surfaces which differ from one another in their coloring. Two significantly different colors, such as for example red and green, have the effect of providing two signaling states which can be clearly distinguished from one another and, by being assigned to the warning in an appropriately agreed fixed manner and an easy-to-interpret way, signal for example whether or not the specific warning is being given. At the same time, the at least two boundary surfaces of the pointer vane may have a different color coating. A colored coating can be realized in a simple and inexpensive way by printing techniques or by corresponding painting, provided that the material and condition of the surface of the pointer vane are suitable for such treatments. An alternative to the colored coating on the pointer vane is to form the pointer vane as a device which changes color in which the boundary surfaces of the pointer vane are provided with a fluorescent print, so that only when they are irradiated with UV light do the boundary surfaces take on a color that is changed in comparison with the unirradiated state. If the pointer vane is formed as a light guide, the boundary surfaces of the pointer vane may also be designed in such a way that light fed into the pointer vane induces a different optical impression according to the angle of rotation of the pointer vane about the axis of its radial extent, so that, for a viewer, for example either the basic color of the body of the pointer vane or the color applied: to its boundary surfaces predominates, or else the color of the light fed into the pointer vane and emerging at the boundary surfaces of the pointer vane predominates.